def test_trans_invar(self):
with pytest.raises(ValueError):
psi = MPS_rand_state(10, 7, cyclic=False, trans_invar=True)
psi = MPS_rand_state(10, 7, cyclic=True, trans_invar=True)
z0 = psi.expec(psi.gate(qu.pauli('Z'), 0, contract=True))
z3 = psi.expec(psi.gate(qu.pauli('Z'), 0, contract=True))
z7 = psi.expec(psi.gate(qu.pauli('Z'), 0, contract=True))
assert_allclose(z0, z3)
assert_allclose(z3, z7)
def test_gate_no_contract(self, bsz, propagate_tags, contract):
p = MPS_rand_state(5, 7)
q = p.copy()
G = qu.rand_uni(2**bsz)
p = p.gate(G,
where=[i for i in range(2, 2 + bsz)],
tags='G',
contract=contract)
TG = p['G']
if propagate_tags or contract:
assert p.site_tag(2) in TG.tags
assert p.H @ p == pytest.approx(1.0)
assert abs(q.H @ p) < 1.0
assert len(p.tensors) == 6 - int(contract) * bsz
assert set(p.outer_inds()) == {'k{}'.format(i) for i in range(5)}
def test_swap_gating(self):
psi0 = MPS_rand_state(20, 5)
CNOT = qu.controlled('not')
psi0XX = psi0.gate(CNOT, (4, 13))
psi0XX_s = psi0.gate_with_auto_swap(CNOT, (4, 13))
assert psi0XX.H @ psi0XX_s == pytest.approx(1.0)